1999 SUZUKI GRAND VITARA o2 sensor

6E2-18 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Air Intake System
Throttle body
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Drain cooling system.
3) Remove strut tower bar.
4) Disconnect accelerator cable (1) and or A/T throttle cable (2)
from throttle body.
5) Disconnect water hoses from throttle body.
1. Throttle body 4. Water hose
2. Intake collector 5. MAF sensor
3. Breather hose 6. TP sensor

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-19
6) Remove surge tank cover.
Remove intake air pipe (1) and surge tank pipe (2).
7) Disconnect connectors of TP sensor and IAC valve.
8) Disconnect ground wire at connector.
9) Remove clamp bracket (1) and harness clamps from intake
collector.
10) Disconnect connectors of EVAP canister purge valve (1),
MAP sensor and EGR valve (5).
11) Disconnect PCV valve (6) from cylinder head with hose con-
nected, breather hose (3) from cylinder head and EVAP can-
ister purge valve hose (2).
12) Detach EGR pipe (4) from intake air collector.
13) Remove throttle body (3) and intake collector (2) from intake
manifold (1).
14) Disconnect hoses of PCV from throttle body.
15) Remove throttle body from intake collector.
NOTE:
TP sensor (4), or other components containing rubber
must not be placed in a solvent or cleaner bath. A
chemical reaction will cause these parts to swell,
harden or get distorted.
Don’t put drills or wires into passages for cleaning. It
causes damages in passages.

6E2-20 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
CLEANING
Clean throttle body bore and bypass air passages (1) by blowing
compressed air.
INSTALLATION
1) Clean mating surfaces and install throttle body gasket to
intake collector (1) with new gasket (2).
2) Install throttle body to intake collector and tighten bolts.
3) Connect PCV hose.
4) Install throttle body and intake collector to intake manifold
with new intake collector gaskets.
5) Install EGR pipe with new gaskets.
6) Connect breather hose and EVAP canister purge valve hose
and install PCV valve to cylinder head.
7) Connect connectors of EVAP canister purge valve, MAP
sensor and EGR valve.
Fix wire harness with clamps.
8) Install clamp bracket to intake collector.
9) Connect ground wire connector.
10) Connect connectors of TP sensor, ground and IAC valve.
11) Install surge tank pipe to intake manifold with new gaskets
and intake air pipe to throttle body. Install surge tank cover.
12) Connect engine coolant hoses to throttle body.
13) Connect accelerator cable and A/T throttle cable (A/T).CAUTION:
Do not blow compressed air through bypass air pas-
sage with IAC valve installed to throttle body. This will
cause IAC valve to malfunction.
TP sensor, idle air control valve or other components
containing rubber must not be places in a solvent or
cleaner bath.
A chemical reaction will cause these parts to swell,
harden or get distorted.

6E2-32 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Mass air flow sensor (MAF sensor)
INSPECTION
1) Connect voltmeter (1) to “B+” terminal of MAF sensor (2)
coupler disconnected and ground (3).
2) Turn ignition switch ON and check that voltage is battery volt-
age.If not, check if wire harness is open or connection is
poor.
3) Turn ignition switch OFF and remove ECM/PCM cover (1)
from bracket.
4) Connect MAF sensor coupler to MAF sensor.
5) Turn ignition switch ON and check voltage at MAF sensor
output terminal of ECM/PCM connector (1).
MAF sensor output voltage
Voltage: 1.0 - 1.6 V
6) Start engine and check that voltage is lower than 5 V and it
rises as engine speed increases.
(Reference data: 1.7 – 2.0 V at specified idle speed)
If check result is not as specified above, cause may lie in
wire harness, coupler connection, MAF sensor or ECM/
PCM. NOTE:
Use voltmeter with high-impedance (10 kΩ
ΩΩ Ω/V minimum)
or digital type voltmeter.

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-33
REMOVAL
1) Disconnect negative (–) cable at battery and coupler (1) from
MAF sensor (3).
2) Remove air cleaner outlet hose (2) from throttle body and
MAF sensor (3).
3) Remove MAF sensor from air cleaner case.
INSTALLATION
1) Check MAF sensor seal (1) for deterioration and damage.
2) Install MAF sensor to air cleaner case.
3) Install air cleaner outlet hose.
4) Connect MAF sensor coupler securely.
5) Connect negative (–) cable to battery.
CAUTION:
Don’t disassemble MAF sensor.
Do not expose MAF sensor to any shock.
Do not blow compressed air by using air gun or the
like.
Do not put finger or any other object into MAF sensor.
Malfunction may occur.

6E2-34 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Intake air temperature (IAT) sensor
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Disconnect IAT sensor coupler.
3) Remove IAT sensor from air cleaner case.
INSPECTION
Immerse temperature sensing part of IAT sensor in water (or ice)
and measure resistance between sensor terminals while heating
water gradually.
If measured resistance doesn't show such characteristic as
shown in the figure, replace IAT sensor.
INSTALLATION
1) Clean mating surface of sensor and seal (2) on air cleaner
case.
2) Install IAT sensor (1) into seal.
3) Connect connector to IAT sensor securely.

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-35
Throttle position sensor (TP sensor)
INSPECTION
1) Disconnect negative (–) cable at battery and coupler from TP
sensor (4).
2) Using ohmmeter, check resistance between terminals under
each condition given in table below.
If check result is not satisfactory, replace TP sensor.
TP sensor specification:
3) Connect TP sensor coupler securely.
4) Connect negative cable to battery.
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Disconnect coupler from TP sensor.
3) Remove TP sensor from throttle body.
INSTALLATION
1) Install TP sensor (1) to throttle body (2).
Fit TP sensor (1) to throttle body (2) in such way that its
holes are a little away from TP sensor screw holes as shown
in the figure and turn TP sensor (1) clockwise so that those
holes align.
Tightening torque
TP sensor screw
(a) : 3.5 N·m (0.35 kg-m, 2.5 lb-ft)
2) Connect coupler to TP sensor securely.
3) Connect battery negative (–) cable to battery. TERMINALS RESISTANCE
Between 1 and
3 terminals4.0 – 6.0 kΩ
ΩΩ Ω
Between 1 and
2 terminals0.02 – 6.0 kΩ
ΩΩ Ω
varying linearly according to
throttle valve opening
1. Ground terminal
2. Output voltage terminal
3. Reference voltage terminal

6E2-36 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Engine coolant temperature sensor (ECT sensor)
REMOVAL
1) Disconnect negative (–) cable from battery.
2) Drain cooling system.
3) Disconnect coupler from ECT sensor (1).
4) Remove ECT sensor from water outlet cap (2).
INSPECTION
Immerse temperature sensing part of ECT sensor in water and
measure resistance between sensor terminals while heating
water gradually.
If measured resistance doesn’t shown such characteristic as
shown in the figure, replace ECT sensor.
INSTALLATION
Reverse removal procedure noting the followings.
•Clean mating surfaces of sensor and water outlet cap (1).
•Use new O-ring.
•Tighten ECT sensor to specified torque.
Tightening torque
ECT sensor (a) : 15 N·m (1.5 kg-m, 11.0 lb-ft)
•Connect coupler to sensor securely.
•Refill cooling system.